Lab - Muscle contraction Flashcards
What is a muscle twitch?
When a muscle is stimulated with a single electric shock of sufficient voltage, it quickly contracts and relaxes
What is muscle summation?
When the first electric shock is given a contraction occurs. If a second one occurs before the electrical potential returns to the resting membrane potential, the second shock ‘piggybacks’ on top of the impulse that is left while repolarising so an even bigger action potential is triggered giving a stronger contraction
What is a tetanic contraction>
Tetanic contraction - A sustained muscle contraction evoked when the motor nerve that innervates a skeletal muscle emits action potentials at a very high rate.
A motor neuron is maximally stimulated by its motor neuron and remains that way for some time. Occurs when a muscles motor unit is stimulated by multiple impulses as a sufficiently high frequency (Tetanic think tetanus gran mal seizure)